• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.28 no.1
• /
• pp.16-23
• /
• 2002

To understand the micro-mechanical changes and the effects of the fluoride on rat's femur after administration of sodium fluoride, the three-point bending test, acoustic emission analysis during the three-point bending test and scanning electron microscopy were performed. The obtained results were as follows: 1. Bone strength increased in the rats given 1, 5, 10 and 20 ppm of fluoride but, there were no statistical significances (p>0.05). 2. With increasing the concentration of fluoride, most AE events released rapidly just before the maximum load and smaller events were recorded than the control group's. The average of cumulative AE event counts until maximum load of the femur in 20 ppm group were significantly small with respect to the control group's (p<0.05). 3. Fracture surfaces were well coincide with the results of acoustic emission behavior. Analyses of fracture surfaces indicated that, consistent with its the highest load, rat femur in 20 ppm fluoride group displays the roughest surface.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.19 no.4
• /
• pp.227-233
• /
• 2019

Background: Dental anxiety in children is a major barrier in patient management. If dental anxiety in pediatric patients is assessed during the first visit, it will not only aid in management but also help to identify patients who are in need of special care to deal with their fear. Nowadays, children and adults are highly interested in multimedia and are closely associated with them. Children usually prefer motion pictures on electronic devices than still cartoons on paper. Therefore, this study was conducted to evaluate a newly designed scale, the animated emoji scale (AES), which uses motion emoticons/animojis to assess dental anxiety in children during their first dental visit, and compare it with the Venham picture test (VPT) and facial image scale (FIS). Methods: The study included 102 healthy children aged 4-14 years, whose dental anxiety was measured using AES, VPT, and FIS during their first dental visit, and their scale preference was recorded. Results: The mean anxiety scores measured using AES, FIS, and VPT, represented as $mean{\pm}SD$, were $1.78{\pm}1.19$, $1.93{\pm}1.23$, and $1.51{\pm}1.84$, respectively. There was significant difference in the mean anxiety scores between the three scales (Friedman test, P < 0.001). The Pearson's correlation test showed a very strong correlation (0.73) between AES and VPT, and a strong correlation between AES and FIS (0.88), and FIS and VPT (0.69), indicating good validity of AES. Maximum number of children (74.5%) preferred AES. Conclusion: The findings of this study suggest that the AES is a novel and child-friendly tool for assessing dental anxiety in children.

• Journal of dental hygiene science
• /
• v.14 no.4
• /
• pp.448-454
• /
• 2014

The aim of this study was to evaluate the effect of a water fluoridation program (WFP) on prevention of dental caries in Gimhae City, Korea, with reference to the results of 2012 Korean National Oral Health Survey (KNOHS). In WFP population, 972 subjects including 8-, 10- and 12-year-old children in Gimhae City were examined in 2009. The WFP in Gimhae city has been implemented since 1999. 1872 subjects in non-fluoridated small and medium sized cities similar to Gimhae city were selected from 2012 KNOHS data as the control population. Two dentists who received training in KNOHS with an inter-examiner-agreement examined oral health status of all subjects. To assess the effects of WFP on dental caries, caries preventive fraction was estimated by assessing the differences of decayed, missing, and filled teeth (DMFT) index and decayed, missing, and filled surfaces (DMFS) index, DMFS in pit and fissures and smooth surfaces between WFP population and the control. Univariate analysis of variance adjusted for gender and number of fissure-sealed teeth or surfaces was conducted. DMFT of 12-year-old subjects (n=354) in WFP and control population (n=1,518) were 1.60 and 2.12, respectively, with an estimated prevention effect of 24.7%. Caries preventive fraction on pit and fissure, and smooth surfaces of WFP subjects was estimated 27.5% and 24.0%, among subjects aged 12 years, respectively. WFP in Gimhae City, Korea reduced the prevalence of dental caries and is recommended as a public oral health program where a fluoride-containing toothpastes are commonly used.

• Journal of Periodontal and Implant Science
• /
• v.45 no.6
• /
• pp.205-209
• /
• 2015

Purpose: Dental implants present several advantages over other tooth replacement options. However, there has been little research on masticatory function in relation to implant treatment. Therefore, the aim of the present study was to evaluate the improvement of masticatory function two weeks after implant restoration. Methods: Masticatory ability was evaluated with the subjective food intake ability (FIA) and objective mixing ability index (MAI) methods. Fifty-four subjects with first and second missing molars completed the study. The subjects were asked to complete a self-reported questionnaire about 30 different food items, and to chew wax samples 10 times both before and two weeks after implant restoration. A total of 108 waxes were analyzed with an image analysis program. Results: Dental implant restoration for lost molar teeth on one side increased the FIA score by 9.0% (P<0.0001). The MAI score also increased, by 14.3% after implant restoration (P<0.0001). Comparison between the good and poor mastication groups, which were subdivided based on the median MAI score before implant restoration, showed that the FIA score of the poor group was enhanced 1.1-fold while its MAI score was enhanced 2.0-fold two weeks after an implant surgery. Conclusions: Using the FIA and MAI assessment methods, this study showed that masticatory function was improved two weeks after implant restoration. In particular, the enhancement of masticatory function by implant restoration was greater in patients with relatively poor initial mastication than in those with good initial mastication.

• The Journal of the Korean dental association
• /
• v.50 no.1
• /
• pp.31-37
• /
• 2012

Objective : This research compared stabilities between two types of dental implant ($SLA^{TM}$, Institut Straumann AG, Waldenburg, Switzerland and $SSII^{TM}$, Osstem co, Busan, Korea) using Osstell Mentor (Integration Diagnostics AB, Goteborg, Sweden) considering surgery methods, surgery area, diameter of implant, systemic disease, and smoking for obtaining prognosis information when installing fixture of dental implant. Materials & Methods : 206 implants of 131 patients taken by resonance frequency analysis (RFA) were determined as a final sample. Dental implants were installed as protocol of supplier by a excellent dentist who had 10 years experience about dental implants. Before connecting abutments (3 months after installation of fixture), RFA were measured twice for buccal and lingual direction to obtain average value. Results : Dental implants at mandible showed significantly higher stabilities significantly than at maxilla (p<0.001). Diameter 4.8 implants had also higher stabilities than diameter 4.1 in case of $SLA^{TM}$ implants (p<0.001). $SLA^{TM}$ implants showed more excellent stabilities than $SSII^{TM}$ implants, especially at posterior area of mandible (p=0.045) and premolar area of maxilla (p=0.032). Conclusions : This research revealed higher stabilities of $SLA^{TM}$ implants than $SSII^{TM}$ implant, especially at posterior area of mandible (p=0.045) and premolar area of maxilla (p=0.032).

• Journal of Korean society of Dental Hygiene
• /
• v.12 no.2
• /
• pp.431-438
• /
• 2012

Objectives : The aim of this study was assessment of the variation of urinary mercury concentrations after removal of amalgam fillings in children. Methods : 10 elemental school children with amalgam filling tooth surfaces were took part in this study. One dentist recorded the number of amalgam filling surface, and general characteristics of subjects were surveyed by questionnaire. Each urine samples were collected before, immediately after and after 24 hours amalgam removal. The statistical analysis was performed using the SPSS 18.0. Results : The mean concentration urinary mercury immediately after amalgam removal was higher ($5.70{\pm}1.20{\mu}g/g$ creatinine) than before amalgam removal ($5.28{\pm}1.53{\mu}g/g$ creatinine). The mean concentration urinary mercury level whose have 1-10 amalgam removal surfaces was increased after amalgam removal compared with before. Conclusions : Mercury concentration in urine was influenced by amalgam removal.

• The Journal of Korea Assosiation for Disability and Oral Health
• /
• v.2 no.1
• /
• pp.10-16
• /
• 2006

The aim of the present study was to investigate the dental caries experience in disabled people according to the handicapped types in Korea. This study subjects based on the national disabled survey 2004 were collected by designed cluster sampling and interviewed with structured questionnaire in order to examine dental caries and sociodemographic status. The subjects were attending the special schools and private or public welfare institutions for crippled disorder, encephalopathy disorder, mental retardation, visual disturbance, and hearing defect. Oral examination was conducted by 13 trained dentists. 1,307 of handicapped people were finally analysed. ANOVA and Cochran-Mantel-Hanzel analysis were adapted for statistical analysis. The results were as follows; Dental caries prevalence, DMFT(Decayed, missing, filled teeth), and DMFS(Decayed, missing, filled surfaces) of disabled people were higher in crippled disorder and mental retardation than the others. There were significant differences in dental caries prevalence, DMFT, and DMFS according to the disabled. DMFT was significantly higher than national population in every age group except in 12-14 year-old and more than 35 group. It was likely that the experience level of dental caries was significantly different according to the handicapped types in Korea and higher than the people without handicap.

• Korean Journal of Health Education and Promotion
• /
• v.33 no.1
• /
• pp.41-48
• /
• 2016

Objectives: This study is aimed to evaluate oral health knowledge and behavior according to subjective awareness characteristics of oral health in university student. Methods: The data was collected from June, 2015 in K university, Korea. It was investigated about subjective awareness characteristics, knowledge and behavior of oral health by questionnaires in university students. The data was analysis into t-test and one-way ANOVA by SPSS 22.0. Results: Subjects who responded that they had a problem with oral health in subjective awareness characteristics were a statistically significant differences according to gender. Subjects who were interested of oral health and responded to their subjective oral health state as good condition were higher than the others in oral health knowledge. According to subjective awareness characteristics of oral health, the oral health behaviors were a statistically significant differences. Conclusions: There were statistically significant differences in oral health knowledge and behavior according to subjective awareness characteristics of oral health.

• The Journal of the Korean dental association
• /
• v.57 no.1
• /
• pp.8-17
• /
• 2018

Purpose : The purpose of this study was to survey the present status of the regional oral health centers for the disabled. Material and methods : Face to face interviews with oral healthcare professionals in eight regional oral health centers and literature reviews were conducted among eight regional oral health centers for the disabled during 2, July to 30, August 2017. Results : It is necessary to establish more regional oral health centers for the disabled in area where the number of disabled person as percentage of whole region population is high. Also, all the centers appeared a lack of professional manpower including dentist, dental hygienist and anesthesiologist, equipment and facilities for the demands of patients and their guardians. It is essential for the government to improve the support system to regional oral health centers for the disabled. Conclusions : This study can be used as a reference for the countermeasure to make a new policy and activate the accessibility of dental care services in the public for the disabled.

• Journal of Korean Academy of Oral Health
• /
• v.43 no.3
• /
• pp.118-123
• /
• 2019

Objectives: The purpose of this study was to investigate changes in the composition of artificial cariogenic biofilms using a Streptococcus mutans biofilm model over a period of time. Methods: We analyzed the dry weight, colony forming unit (CFU) number, extracellular polysaccharide (EPS) biovolume, and acid production rate of S. mutans biofilms formed on saliva-coated hydroxyapatite discs after 26 h, 50 h, 74 h, 98 h, 171 h, and 195 h. In addition, we performed a laser scanning confocal fluorescence microscopy to determine the bacterial volume, EPS biovolume, and biofilm thickness. We calculated the biofilm density using dry weight and EPS biovolume. Results: Over a period of time, there was no change in the CFU number and acid production rate of S. mutans biofilms, but there was an increase in the dry weight and EPS biovolume of S. mutans biofilms. The bacterial volume, EPS biovolume, and biofilm thickness only increased in the 50-h-old biofilm; however, no change was observed in 50-195-h-old biofilms. In addition, an increase in the biofilm density was observed over time. Conclusions: These results suggest that the acid production ability of cariogenic biofilms does not change, but the biofilm density increases over time. However, due to scientific information, further research needs to be conducted in the field of dentistry to get further insights on the progression of cariogenic biofilms over time.